To mitigate tower crane collapse risks during typhoon events, this study investigates the optimal overhanging height ratio (OOHR) for two tower structures: a uniform-section tower with a flexible tie-in structure and a stepped-column tower with a rigid tie-in structure. Employing differential equation methods, the equivalent stiffness provided by the lower tower section to the upper section was derived. By introducing two dimensionless coefficients - the flexible tie-in structure stiffness coefficient and the inertia moment ratio between tower sections, the principle of equal maximum bending moments is applied between the tied-in cantilever tower segment and the independently working maximum-height segment. Functional relationships between these coefficients and the overhanging height ratio were established. The analysis shows that for axial force coefficients ranging from 0.01 to 0.2, variations in flexible tie-in stiffness exert negligible influence on the overhanging height ratio, and significant differences exist between the OOHRs for flexible and rigid tie-in structures within this range. Meanwhile, for a stepped-column tower with a rigid tie-in structure, the inertia moment ratio of the tower's upper part to the lower shows a positive correlation with the OOHR. Under the condition of identical axial force coefficients, the OOHR of a stepped-column tower with a rigid tie-in structure is consistently smaller than that of a uniform-section tower with a flexible tie-in structure. Both configurations yielded OOHRs exceeding the stability-based ratios derived for rigid-tie-in towers under normal working conditions. Therefore, under typhoon conditions, the OOHR of a tower crane with a tie-in structure can be determined based on the stability criterion established for rigidly tied-in towers under normal working loads.